Moyamoya disease: comparison of assessment with MR angiography and MR imaging versus conventional angiography.

PURPOSE: To evaluate magnetic resonance (MR) angiography and MR imaging in assessment of moyamoya disease. MATERIALS AND METHODS: The cases of 26 patients with moyamoya disease were evaluated prospectively. After three-dimensional time-of-flight 1.5-T MR angiography and MR imaging, images were evaluated in blinded separate interpretation. RESULTS: MR angiography and MR imaging accurately depicted 217 (82%) and 184 (70%) of 264 arteries, respectively, but the degree of stenosis was overestimated in the other arteries. Basal cerebral moyamoya vessels were depicted in all 52 hemispheres with conventional angiography and in 42 (81%) and 48 (92%) hemispheres with MR angiography and MR imaging, respectively. The respective sensitivity and specificity for diagnosis of moyamoya disease were 73% and 100% for MR angiography, 92% and 100% for MR imaging, and 92% and 100% for MR angiography plus MR imaging. CONCLUSION: Assessment of moyamoya disease is most thorough with MR angiography and MR imaging.